A broadcast router allows each one of a plurality of outputs therefrom to be assigned the signal from any one of a plurality of inputs thereto. For example, an N×M broadcast router has N inputs and M outputs coupled together by a router matrix which allows any one of the N inputs to be applied to each one of the M outputs. Many such broadcast routers, in particular, the larger broadcast routers, are comprised of a single chassis which houses plural printed circuit boards, commonly referred to as “cards”, interconnected in a wide variety of configurations. Oftentimes, many of the cards housed within a broadcast router are replicas of other cards housed within that same broadcast router. For example, in co-pending U.S. patent application Ser. No. 60/374,976 and previously incorporated by reference, a 1280×1280 broadcast router was disclosed which, when constructed, requires the use of 40 identically configured input cards, each having 32 inputs per card.
Typically, one or more field programmable gate arrays (or “FPGAs”) reside on such cards. An FPGA is an integrated circuit that can be programmed in the field after manufacture. When a card, for example, the aforementioned input card, carrying one or more FPGAs is powered, for example, by power-up a broadcast router in which the card had been installed or by inserting (or “hot-plugging”) the card into a slot in an input/output (or “I/O”) bus of the broadcast router after power-up, the FPGAs residing on that card must be configured. Traditionally, FPGAs have been configured by a storage device, for example, a programmable read only memory (or “PROM”), which resides with the FPGA on that card. However, configuring FPGAs in this manner causes the requisite configuration circuitry and data storage devices to be replicated on each card carrying FPGAs or other programmable devices requiring configuration. Such configuration techniques can prove expensive, particularly for broadcast routers or other systems which include multiple cards on which devices requiring configuration reside.